Replying to Msnow spacing for a drop in

Im building a 6ft high 9ft long drop in using msnow, but I've seen people skip msnow at the top and space it out, and not at the bottom; the issue is I've designed it so the msnow is horizontally on 8in boards, and spaced out 4in between each board. Do I need to buy the medium kit and cover the flat and lip in msnow for the drop in to work and have proper speed, or will a small be enough and I can space out the msnow coverage on the takeoff?
Here are the measurements:
Slope 1 is 3ft long and a 5ft drop, so 70in of surface
Slope 2 is 2ft long and a 1ft drop, 27in of surface
3 is the flat section, 2ft long
The lip is 2ft long, 1ft high, 27in of surface